Belt conveyor systems are employed to convey a great variety of bulk loads between various storage units along a horizontal and gently inclined or declined path. Such belt conveyor systems are commonly used to carry mining materials, food grains, and building materials. A typical belt conveyor system includes a driving pulley at a head end, and a take up pulley at a tail end, both being accommodated in a rigid frame. An endless belt connects the two pulleys on both a conveying run and a returning run, and is supported by suitable roller type supports, called idlers.
In certain applications, the material being conveyed is loaded on the belt conveyor system by one or more feed hoppers mounted over the belt conveyor system, and typically disposed at the tail end. The material load conveyed by the moving belt is then discharged over the driving pulley into a discharge spout. However, the material being conveyed can be loaded and/or discharged at any point, or multiple points, along the conveying run. A take up arrangement is disposed at the tail end of the belt conveyor system to keep the belt under a minimum tension so that the belt does not slip over the pulleys due to extension of its length.
A troughed belt conveyor system is that in which the belt forms a trough on a carrying side while running over the idlers and is substantially planar on a return side while running over a return roller. Each of the idlers includes rollers having a shaft journaled in bearings. The shafts and bearings are prone to buildups of dust or particulates. Such buildup on the bearings may lead to increased friction and bearing failure, which can cause ignition of the combustible dust or particulates. Additional lubrication of the bearings to mitigate against bearing failure may lead to further buildup of dust and leakage of the additional lubrication onto the material being conveyed, resulting in contamination thereof.
It would be desirable to produce a bearing arrangement for a belt conveyor system which enhances equipment maintenance and safety, as well as militates against equipment failure and exposure to combustible dust and particulates, and material contamination.